Mad sounding chef attempted power grab (6)

I believe the answer is:

cuckoo

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'mad' is the definition.
(thesaurus)

I cannot understand how the remainder of the clue works.

(Other definitions for cuckoo that I've seen before include "Onomatopoeic bird" , "that can emerge at hourly intervals" , "slightly mad type" , "Bird which lays eggs in others' nests" , "Hourly you might hear this" .)

I've seen this clue in The Irish Times.

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